There's also a pendant portrait of Helena. They were hung in the Queen's sitting room at Windsor Castle:
You can see them rto the lower sides of the Winterhalter family portrait. Louise was on the right side of the photo.
Also in the sitting room are portraits of Alfred, Victoria & Albert in costume, Victoria of Hesse, Charlotte of Wales, Arthur & Edward VII, Empress Eugenie and one of the Indian servants with Alexander and Ena Battenberg as well as the miniatures of her children on the firescreen. There are photos on her table of the Duchesses of Edinburgh and Albany.